﻿ Pandas styling: Write a Pandas program to highlight the negative numbers red and positive numbers black - w3resource

# Pandas styling Exercises: Write a Pandas program to highlight the negative numbers red and positive numbers black

## Pandas styling: Exercise-1 with Solution

Create a dataframe of ten rows, four columns with random values. Write a Pandas program to highlight the negative numbers red and positive numbers black.

Sample Solution :

Python Code :

``````import pandas as pd
import numpy as np
np.random.seed(24)
df = pd.DataFrame({'A': np.linspace(1, 10, 10)})
df = pd.concat([df, pd.DataFrame(np.random.randn(10, 4), columns=list('BCDE'))],
axis=1)
print("Original array:")
print(df)
def color_negative_red(val):
color = 'red' if val < 0 else 'black'
return 'color: %s' % color
print("\nNegative numbers red and positive numbers black:")
df.style.applymap(color_negative_red)
``````

Original array:

```Original array:
A         B         C         D         E
0   1.0  1.329212 -0.770033 -0.316280 -0.990810
1   2.0 -1.070816 -1.438713  0.564417  0.295722
2   3.0 -1.626404  0.219565  0.678805  1.889273
3   4.0  0.961538  0.104011 -0.481165  0.850229
4   5.0  1.453425  1.057737  0.165562  0.515018
5   6.0 -1.336936  0.562861  1.392855 -0.063328
6   7.0  0.121668  1.207603 -0.002040  1.627796
7   8.0  0.354493  1.037528 -0.385684  0.519818
8   9.0  1.686583 -1.325963  1.428984 -2.089354
9  10.0 -0.129820  0.631523 -0.586538  0.290720

Negative numbers red and positive numbers black:
```

Sample Output:

```
```

Python Code Editor:

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## Python: Tips of the Day

Python: Annotated Assignment Statement

This might not seem as impressive as some other tricks but it's a new syntax that was introduced to Python in recent years and just good to be aware of.

Annotated assignments allow the coder to leave type hints in the code. These don't have any enforcing power at least not yet. It's still nice to be able to imply some type hints and definitely offers more options than only being able to comment regarding expected types of variables.

```day: str = 'Monday'
print(day)
lst: list = [1,2,3,4]
print(lst)
```

Output:

```Monday
[1, 2, 3, 4]```

Or the same thing in a shorter way:

```day= 'Monday' #str
print(day)
lst= [1,2,3,4] # list
print(lst)
```

Output:

```Monday
[1, 2, 3, 4]```